The present invention relates to a method for increasing the number of stitches of a rib knit fabric using knitting needles of front and rear needle beds on flat knitting machine.
In knitting a fabric with a flat knitting machine, it is known to increase the stitches for shaping a knitted fabric with addition of wales.
For increasing the stitches, there are two major methods: one for making an increased stitch on an unoccupied knitting needle located outside the end of a row of stitches to extend the length of the row and the other for shifting a predetermined number of stitches of a row including a stitch at the end of a row in an outside direction to make unoccupied knitting needles, intermediate of the knitted row and forming loops on the unoccupied knitting needles.
In the former method, the edge of a knitted fabric is added with a new wale upon increasing stitches and will hardly be arranged neatly. The latter method produces additional wales in the middle of a knitted fabric, thus leaving the selvages at both edges intact.
Apparently, the latter method is advantageous over the former method in appearance and efficiency for joining a plurality of knitted fabrics to each other and is now widely used for fabricating common garments.
With the use of such a two-needle-bed type flat knitting machine in the present invention, stitches can be increased on both the front and rear needle beds simultaneously and equally.
A conventional method will be explained referring to a rib knitting shown in FIG. 10.
After repeating, a desired number of times, a couple of courses, as shown in FIG. 10-1 and 10-2, rows of stitches are completed forming a size of rib fabric. Then, the loop on the knitting needle B at the end of the last row of the rib knit fabric is transferred to a knitting needle a next to the opposite knitting needle b of the rear needle bed. After the rear bed is racked to the direction of the knitting needle a (to the left in the drawings), the loop is moved from the knitting needle a to a knitting needle A of the front bed. As the result, the loop is shifted from the needle B to the needle A in the leftward direction and the needle B becomes unoccupied.
By repeating this procedure on each loop with a series of racking actions, a desired number of loops of the row are shifted to the left so that as shown in FIG. 10-3, the two opposite knitting needles F and f hold no thread of yarn as shown in FIG. 10-3.
In the next step shown in FIG. 10-4, the thread is passed along the front knitting needles A to P, and the rear knitting needles a to p alternately, as a carriage of the flat knitting machine travels forward.
Accordingly, all the knitting needles, except F and f, hold knit stitches. Because of no thread supplied to needles F and f in the preceding course, the two knitting needles F and f have the thread not looped but just hooked.
Similarly, the loops on the knitting needles L to P and 1 to p of the front and rear beds, respectively, are shifted to the rightward direction with a series of racking actions in order to make increased stitches on the two knitting needles L and 1. As the result, the knitting needles L and 1 hold no threads as shown in FIG. 10-5.
In the succeeding step shown in FIG. 10-6, the thread is passed along the front knitting needles A to Q and the rear knitting needles a to q alternately throughout the width of a knitted fabric.
According to the conventional method, the thread is supplied to the unoccupied knitting needles F and f as the carriage travels in the forward direction.
Since no stitches are formed on the knitting needles F and f in the preceeding course, the thread 2 extending from the front knitting needle F to the rear knitting needle f remains not engaged with the thread 1 supplied in the preceding course, unlike the thread to any of the other knitting needles.
It will thus be likely that stitches formed on the knitting needles F and f in the succeeding course is pulled up by stitches formed in the further course.
As the result, a gap or hole appears where the increased stitches are formed thus deteriorating the quality of a finished knitted product.